The main objective of the research project is to elucidate some of the mechanisms and interactions that regulate the temporal behavior, particularly circadian, of specific rhythmically active neurons, and further to study the effects of temporal sequencing stimuli. The nervous system of Aplysia, a marine gastropod, will be studied with electrophysiological techniques at the single identifiable neuron and group of neurons levels. Tissue culture techniques will be employed to allow long term recording as well as acute recording of electrical activity.